They are only dependent on our high level chip making technology and as I said in the early stages of this debate, the chip manufacturing on Taiwan will be the underlying driver for China to reclaim Taiwan. It is much easier to take over existing than design and develop your own technology.
When the U.S entered the Second world war, the industrial hubs of America were huge, massive steel making from the railroad development, the steel manufacturing for all the car manufacturing and sky scraper building. Those days, as with the U.K and Australia are long gone, 90% of the pig iron blast furnaces and steel furnaces and rolling mills are gone, to rebuild them can't be done in 12 months, it takes years, the supporting infrastructure has been removed, rail supply lines, gas lines, raw material unloading plant etc. I know I worked in a blast furnace in the 1970's, it has been gone for 40 years and something completely different is in its place.
the U.S currently has about 40 remaining blast furnaces, China has 260 fully operational, from memory I think Australia has two still operational.
We would struggle to arm our military with enough small arms and ammunition to last any length of time, let alone arm civilians, we don't even have gun and ammo shops anymore so where would we get it from?
Let's not pretend.
The West has made a lot of money out of offshoring their manufacturing to third world countries for cheap labour, they increased their lifestyle from poverty, ours went up a huge amount on importing cheap goods rather than producing them in our own country and paying high wages. It wasn't driven by good nature, it was driven by making stuff we wanted cheaper it's just good business.
That doesn't mean it is good practice, it has left the West with a massive exposure to critical supplies, covid highlighted it and now China is exploiting it, that's life you know for every action there is a reaction how that manifests is the only difference.
The West has to form strong alliances, because we have gutted out our manufacturing capability, so we are going to have to work together to piece together enough capacity to hopefully make some sort of deterrent.
The saving grace at the moment is, China doesn't know what high tech weapons the U.S has, so it is still not confident and that is why Xi is demanding China focus on improving its home grown high tech capability.
If China was confident, Taiwan would already be done and dusted, meanwhile as I said a couple of years ago Taiwan chip manufacturing will be getting dismantled. Just my opinion.